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Reliability-based Detection of Variable-rate Space-time Block CodesKiarashi, Nooshin 27 September 2008 (has links)
We present a new sub-optimal near-maximum-likelihood (ML) detection
method for the family of variable-rate space-time block codes
(VRSTBC). The proposed detection method is based on the concept of
symbol reliability and provides a wide range of
performance-complexity trade-offs. The reliability measures are
defined with the help of a recent generic ML metric expression. The
error performance and complexity analysis of the method via
simulations show an achievable near-ML error performance with
significant reduction in complexity. The performance of the proposed
method is also compared with the group interference cancellation
(GIC) method which was the detection method originally applied to
VRSTBCs and the results show a significant improvement. The new
method offers various levels of error protection via a simple
parameter and hence can provide the users of a wireless network with
different performance levels according to their cost allowance.
Unequal error protection by VRSTBCs under the new detection method
was explored. Several applications integrating data with different
levels of sensitivity to error can benefit from the wide range of
possibilities that the combination of the proposed detection method
and VRSTBCs provides. To further explore these flexibilities, four
practically interesting power allocation schemes were applied to the
transmission and the behaviors were observed through case studies. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2008-09-26 23:45:07.81
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BANDWIDTH LIMITED 320 MBPS TRANSMITTERAnderson, Christopher 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / With every new spacecraft that is designed comes a greater density of information that will
be stored once it is in operation. This, coupled with the desire to reduce the number of
ground stations needed to download this information from the spacecraft, places new
requirements on telemetry transmitters. These new transmitters must be capable of data
rates of 320 Mbps and beyond.
Although the necessary bandwidth is available for some non-bandwidth-limited
transmissions in Ka-Band and above, many systems will continue to rely on more narrow
allocations down to X-Band. These systems will require filtering of the modulation to meet
spectral limits. The usual requirements of this filtering also include that it not introduce
high levels of inter-symbol interference (ISI) to the transmission.
These constraints have been addressed at CE by implementing a DSP technique that pre-filters
a QPSK symbol set to achieve bandwidth-limited 320 Mbps operation. This
implementation operates within the speed range of the radiation-hardened digital
technologies that are currently available and consumes less power than the traditional high-speed
FIR techniques.
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